Kitz: Your having sent this announcement all over the world may well constitute a breach of national security.Ellie Arroway: This isn't a person-to-person call. You can't possibly think that a civilization sending this kind of message would intend it just for Americans.Kitz: I'm saying you might have consulted us; obviously, the contents of this message could be extremely sensitive.Ellie Arroway: You want to classify prime numbers?